Question

Which of the following samples will have the greatest volume at STP?a. 22 g Neb. 22 g Hec. 22 g O2d. 22 g Cl2 e. All have the same V at STP

Answer 1

Answer:

22g of He

Explanation:

Volume of gas at STP is given as :

Volume occupied(dm³) = number of moles x 22.4dm³mol⁻¹

In order to solve this given problem, we would first find the number of moles from the different masses of atoms and molecules given.

Number of moles = $\frac{mass }{Molar mass}$

Now, let us obtain the molar mass of the given atoms and elements:

For Ne; molar mass is the atomic mass = 20gmol⁻¹

      He = 4gmol⁻¹

      O₂ = (16 x2)gmol⁻¹  = 32gmol⁻¹

      Cl₂ = (35.5x2)gmol⁻¹ = 71gmol⁻¹

Number of moles of Ne = $\frac{22}{20}$ = 1.1mol

Volume occupied by Ne at STP = 1.1 x 22.4 = 24.64dm³

       

Number of moles of He = $\frac{22}{4}$ = 5.5mol

Volume occupied by He at STP = 5.5 x 22.4 = 123.2dm³

Number of moles of O₂ = $\frac{22}{32}$  = 0.688mol

Volume occupied by O₂ at STP = 0.688 x 22.4 = 15.4mol

Number of moles of Cl₂ = $\frac{22}{71}$ = 0.3099mol

Volume occupied by Cl₂ at STP = 0.3099 x 22.4 = 6.94dm³